Many systems currently exist for mounting photovoltaic arrays onto trapezoidal metal roofs (a roof type that is especially common in Europe). Unfortunately, these existing systems often are complex, involve many parts and take an undesirably long time to install. Moreover, the installation of these systems typically requires specialized tools, or a number of different tools. What is instead desired is a mounting system that can be installed very rapidly on a metal roof and is also easily handled by an installer.
Trapezoidal roof mounting systems are not secured into building rafters. Instead, they are usually secured to the metal roofing material itself above the rafter. This is because the rafters typically nm perpendicular to the peaks of the metal roofing material. As a result, these systems must be firmly attached directly to the metal roofing surface. In most existing systems, screws are inserted through the metal roof, which can present several problems. First, working with small screws typically involves the installers fumbling with parts during the installation, as the installer tries to position and fasten them, but it is also important that the screw-to-metal-roof connection be sufficiently strong so that the array is held firmly in place. Second, a problem with existing systems is that they need to have sufficient flexibility to account for movement of parts of the array caused by thermal expansion and contraction. This problem is not typically well addressed in mounting systems that are simply screw-fastened onto metal roofs. Third, existing trapezoidal roof mounting systems typically require excessive time to install, due to the number of parts required. Fourth, existing trapezoidal roof mounting systems do not typically address module-to-module grounding since separate grounding wires typically need to be attached to the mounting system.